Newts Monitoring This section describes the metrics Horizon collects for monitoring the Newts keyspace from org.apache.cassandra.metrics.Keyspace on a Cassandra node. JMX must be enabled on the Cassandra nodes and made accessible from Horizon to collect these metrics ( see Enabling JMX authentication and authorization). The data collection is bound to the agent IP interface with the service name JMX-Cassandra-Newts. The JMXCollector retrieves the MBean entities from the Cassandra node. All memory table data size Name Description AllMemtablesLiveDataSize Total amount of live data stored in the memtables (2i and pending flush memtables included) that reside off heap, excluding any data structure overhead. AllMemtablesOffHeapDataSize Total amount of data stored in the memtables (2i and pending flush memtables included) that resides off heap. AllMemtablesOnHeapDataSize Total amount of data stored in the memtables (2i and pending flush memtables included) that resides on heap. Memtable switch count Name Description MemtableSwitchCount Number of times flush has resulted in the memtable being switched out. Memtable columns count Name Description MemtableColumnsCount Total number of columns present in the memtable. Memory table data size Name Description MemtableLiveDataSize Total amount of live data stored in the memtable, excluding any data structure overhead. MemtableOffHeapDataSize Total amount of data stored in the memtable that resides off heap, including column-related overhead and partitions overwritten. MemtableOnHeapDataSize Total amount of data stored in the memtable that resides on-heap, including column-related overhead and partitions overwritten. Read and write latency Name Description ReadTotalLatency Local read metrics WriteTotalLatency Local write metrics Range latency Name Description RangeLatency 99th Percentile Local range slice metrics 99th percentile Latency Name Description CasCommitTotalLatency Time spent in Casandra commits since process start. CasPrepareTotalLatency Time spent in Casandra prepare events since process start. CasProposeTotalLatency Time spent in Casandra propose events since process start. Bloom filter disk space Name Description BloomFilterDiskSpaceUsed Disk space bloom filter uses. Bloom filter off-heap memory Name Description BloomFilterOffHeapMemoryUsed Off-heap memory bloom filter uses. Newts memory used Name Description CompressionMetadataOffHeapMemoryUsed Off-heap memory compression metadata uses. IndexSummaryOffHeapMemoryUsed Off-heap memory index summary uses. Pending Name Description PendingCompactions Estimated number of pending compactions for this column family. PendingFlushes Estimated number of pending flushes for this column family. Disk space Name Description TotalDiskSpaceUsed Total disk space used by SSTables belonging to this column family including obsolete ones waiting to be garbage collected. LiveDiskSpaceUsed Disk space used by SSTables belonging to this column family. Cassandra Monitoring RRD/JRB to Newts Migration Utility